Techniques for retaining security restrictions with file versioning

1. A machine-implemented method, comprising: receiving a first instruction to establish a first version of a file; archiving the first version along with a directory path and first access restrictions associated with the first version, wherein the directory path and the first access restrictions are native to the first version, the first version archived to an archive volume; receiving a second instruction to establish a second version of the file; archiving the second version of the file along with the directory path and second access restrictions associated with the second version, wherein the second version archived to the archive volume, and wherein the first version along with the first access restrictions are archived and the second version along with the second access restrictions are archived and then each version is indexed to a particular subdirectory within the archive volume by hashing full paths for each version including server name and directory name and a first portion of each version's file name is retained with an appended time stamp, the full paths hashed to multiple index files, each index file including a particular portion of hash values for the full paths; generating a delta data structure that when applied to the second version permits the first version to be reproduced, the second version is a most recent version of the file whereas the first version is for a prior version of the file occurring before the most recent version of the file, the delta data structure applied to the most recent version to obtain the prior version, wherein the delta data structure records information and instructions in a normalized format that permits the prior version to be obtained from the most recent version; retaining the delta data structure; and deleting the first version from the archive volume having the first version.

2. The method of claim 1 further comprising: receiving an access request from a user for the file to access the first and second versions; producing the directory path along with listings within the directory path for the first version and second version, each listing including unique date and time stamp for when that particular version was versioned; establishing the first and second access restrictions for each of the versions; and presenting the directory path with the listings with the first and second access restrictions being enforced to the user.

3. The method of claim 2 further comprising, denying the user access to the second version when the second access restrictions do not permit the user to access the second version.

4. The method of claim 2 further comprising: granting the user access to the first version when the first access restrictions permit the user to access the first version; and applying the delta data structure against the second version to produce the first version that is presented to the user for access.

5. The method of claim 1 , wherein generating further includes representing the delta data structure to include data that was deleted from the first version when moving to the second version and to include just an indication of where new data was added in the second version from that which was originally in the first version without including the new data in the delta data structure.

6. The method of claim 1 further comprising, receiving an access request from a user for the file to access the first and second versions; producing the directory path along with listings within the directory path for the first version and second version, each listing including unique date and time stamp for when that particular version was versioned; establishing the first and second access restrictions for each of the versions; and presenting the directory path with a first listing for the first version to the user and hiding a second listing for the second version from the user when the second access restrictions indicate that the user is not to be able to see the second version.

7. The method of claim 1 , wherein retaining further includes adding a descriptive string to a front portion of the delta data structure that permits the delta data structure to be recognized as a derivative of the second version that has to be applied to the second version to acquire the first version of the file.

8. A system, comprising: a versioning service implemented in a computer-readable medium as instructions and to process on a server machine of a network; and a delta file control service implemented in a computer-readable medium as instructions and to process on the server machine and one or more additional machines of the network; wherein the versioning service is to version files by retaining native directory paths for those files and retaining native metadata for those files and directories associated the directory paths, the metadata includes access restrictions for accessing the files and the directories, wherein the native metadata includes the access restrictions for accessing the files and the directories for the files as they natively existed before being versioned, and wherein the delta file control service is to retain as a full file, just a most-recent version of any particular file and manage prior versions of that full file as delta data structures that when applied to the most recent version produces a particular prior version, and wherein each particular version of a particular file includes its own unique access restrictions that is enforced when an access attempt is made, wherein the versioning service is to house the files along with their native metadata and their native directory paths in hashed subdirectories on an archive volume that are hashed in response to names associated with the files and the native directory paths and time stamps, the hashed subdirectories stored in multiple index files, each index file include a particular portion of hash values for the hashed subdirectories.

9. The system of claim 8 , wherein the versioning service reconstructs the names and native directory paths along with date and time stamps when a request for access is processed.

10. The system of claim 8 , wherein the delta file control service is periodically processed at configurable intervals.

11. The system of claim 8 , wherein the versioning service uses a restore application programming interface to restore the files that represent backed up data and the access permissions associated with the files once restored.